The United States once again called for dialogue between the government of Iraq and the Kurdistan Regional Government (KRG) to resolve the outstanding issues.

Spokesperson of the U.S. State Department, Heather Nauert said during a press conference on Tuesday (December 5) that Washington will also be willing to help facilitate talks between Erbil and Baghdad if asked.

"It's not the place of the U.S. Government to force these talks to happen. But we do firmly believe that that is the right thing to do and it should happen," Nauert added.

"We just continue to call on the Government of Baghdad and also the Kurds to sit down and have a conversation together."

The Kurdistan Region Prime Minister, Nechirvan Barzani said that no political or technical negotiation has taken place between Baghdad and Erbil so far, expressing the region's commitment to Iraq unity and the constitution.

Tensions between the KRG and the central government hit a high in 2015, after officials from both sides accused each other of failing to abide by the terms of an oil revenue sharing deal struck by officials in December 2014.

Relations hit their lowest in the aftermath of the referendum held by the Kurdistan Region, which saw over 90 percent of voters say "yes" to independence.